Self-started Kerr-lens mode-locked thin-disk oscillator.

Kerr-lens mode-locking (KLM) has been widely used in thin-disk oscillators to generate high-power femtosecond pulses. Here we demonstrate a Kerr-lens mode-locked Yb:YAG thin-disk oscillator that can be self-started under two configurations. The first can deliver 13-W, 235-fs pulses at a repetition rate of 103 MHz; the second delivers 49 W at a repetition rate of 46.5 MHz, whose corresponding pulse energy of 1.05 µJ is, to the best of our knowledge, the highest energy ever obtained in self-started Kerr-lens mode-locked oscillators. A new method to initiate KLM in the form of optical perturbation in a thin-disk oscillator has also been demonstrated.